The present invention relates to a method of and a device for evaluation of vision.
It is known that a human eye and in particular retinae has an area of highest resolution and best color determination--its central cavity of fovea. The latter contains densely located receptors which are sensitive to color. Fovea which possesses highest information capability has the size of 2.degree.. Smallness of this part is compensated by eye's ability to perform sharp jump-like movements by an angle up to 20.degree.. Because of this images of areas of observation are successively projected into the fovea, and therefore the sharpness of vision is distributed over larger field that the area of fovea. In addition, objects which move with angular speeds which are close to the angular speed of eye movement during the jumps become recognizable despite the fact that at these angular speeds they are not only not recognizable, but even flickering of them cannot be seen.
Jump-like movements of eyes takes place at an average of 2-5 times per second. The values of time intervals between two successive eye jumps are distributed randomly, which precludes flickering of images. Frequency and speed of jump-like movements of eyes are different for different people and change with ago and health changes. Evaluation of jump-like movements of individuals is very important for evaluating their vision. Objective evaluation of frequency (average statistic frequency) and speed of jump-like movement of eyes is very important for determining whether given individuals are capable and can be permitted to do certain jobs which require a wide angle of vision, high shaprness of vision, and fast reaction. It can also be used for controlling health of patients in insurance systems.
It is known for purely scientific purposes to investigate jump-like eye movement by a light beam reflected from a mirror which is attached to the eye of a patient. This is a very complicated and dangerous procedure which cannot be use by ophtalmologists for regular eye examinations especially of great number of people. Moreover an eye with the attached mirror does not provide objective results since it acts in abnormal manner.